US President Barack Obama urged young people not to "pull back" from the world and to reject cynicism and xenophobia during a Q&A in London.
Obama's comments came after he faced criticism from leading Brexit campaigners, who branded him an irrelevant "lame duck", over a speech he made supporting the UK's membership of the EU.
Barack Obama has said that in the event of a Brexit, a US-UK trade deal is "not going to happen any time soon."
The US President, responding to a question by ITV News Political Editor Chris Ship at a joint press conference with David Cameron, said that the US will be focusing its attention on reaching an agreement with the EU.
"No man is an island," he added.
Barack Obama has warned that Britain's influence on the global stage would be diminished if it votes to leave the EU.
The presidential hopeful says she agrees with Obama comments adding that she 'has always valued a strong UK in a strong EU'.
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